Translating device for transmitting and receiving coded messages



April 16, 1957 R. DREYSE TRANSLATING DEVICE FOR TRANSMITTING AND RECEIVING CQDED MESSAGES 2 Sheets-Sheet 1 Filed Aug. 18, 1953 v ii 5 6 u e h b x 5 V c u r U 6 s c y b w d q U c e v 6 f j l g i m k p n r u z r u b w s e v t c l g u 2 d y ii f h p 6 j n x i m E] o q k 7 o x h t 10 c f v b x u w i l 6 h p j q d U y e k u o m r n g t z 6 s 11 m q 6 r b w o x t p y s u g u d z c 6 f ii j i l v h n k e 12 6 v j L (j u u w 9 q r t c i s e h d f x n k 0 z b m p y 5 E 9 q i s x w r d ii e b t k v u f j g l 2 U h y 6 c n o y p mg i INVENTOR. RICHARD DREYSE AGENT April 16, 1957 R. DREYSE 2,789,159 TRANSLATING DEVICE FOR TRANSMITTING AND RECEIVING CODED MESSAGES Filed Aug. 1a, 1953 2 Sheets-Sheet 2 I [11 [10 12 T 1 14 MONITORING CODE PRINTING TRANSMIFRECIVE PRINTING 1 5 RECEIVER CODE TRANSLATOR RECEIVER 30b 29 rbnflzf IFF .5

United States Patent TRANSLATING DEVICE FOR TRANSMITTING AND RECEIVING CODED MESSAGES Richard Dreyse, Berlin-Sudende, Germany Application August 18, 1953, Serial No. 374,848 Claims. (Cl. 178-22) My present invention relates to a device for sending out and receiving telegraphic messages wherein, for the purpose of secrecy, the letters of the normal alphabet are interchanged in accordance with a continuously varying code known only to the parties communicating with each other.

The translation of the clear or uncoded message text into its coded equivalent and the subsequent retranslation at the receiving end can be effected, in known manner, by the use of a coding or decoding device comprising a cylinder whereon the various exchange alphabets are arranged according to a predetermined coding or decoding table. These cylinders ordinarily are composed of a plurality of disks, one for each letter of the alphabet or other message character, which are rotated in unison by one or more steps after each coding or decoding operation whereby a new exchange alphabet will take the place of the one previously used. Reference may be made to British Patent No. 341,073, issued to Richard Michel and myself, for a detailed disclosure of a system of this character.

Corresponding exchange alphabets of associated coding and decoding cylinders are not identical but are complementary to each other; i. e., where one shows an A in the L position, there the other will have an L in the A position, and so on. On account of this relationship, it has heretofore been thought necessary to provide separate coding and decoding cylinders which had to be interchanged when a translating device was to be switched from sending to receiving or vice versa, thus resulting in inconvenience and delay.

A principal object of my invention is to provide means for coding and decoding messages in the aforedescribed manner with the aid of a single translating cylinder at the transmitting end having a substantially identical counterpart at the receiving end. Other, ancillary objects of my invention are the provision of means for advantageously arranging and mounting the code disks forming part of a translating cylinder as set forth above.

A feature of my invention resides in a division of the translating cylinder, or of each disk 'thereof, into two complementary parts whose exchange alphabets are the transmit-receive counterparts of one another. Hence, this cylinder may be used, starting from a given position, as part of a coding transmitter and, starting from a difierent position, as part of a decoding receiver. Both sets of alphabets can be used in both the transmitting and the receiving operations.

Since a translating cylinder according to the invention must carry each exchange alphabet in its original as well as in its complementary form, the total number of available exchange alphabets will always be even. For the purpose of increasing the number of coding possibilities by changing the rate of between-letter advance it is, however, desirable to provide the cylinder with an odd or, preferably yet, a prime number of dilferent angular operating positions. This can be accomplished,

Patented Apr. 16, 1957 according to another feature of my invention, by inserting an uncoded or clear" alphabet (or an odd number of such alphabets) among the exchange alphabets of the cylinder; since the clear alphabet is its own complement, no duplication thereof will be required on the cylinder. The presence of the clear alphabet also enables the device of my invention to be used for the sending and/or receiving of uncoded messages by adjusting the cylinder to the proper angular position and thereafter inactivating the advance mechanism.

The invention will be described in greater detail with reference to the accompanying drawing in which:

Figs. 1 and 2 illustrate schematically the arrangement of the exchange alphabets on the translating cylinders of two intercommunicating stations incorporating the invention;

Figs. 3 and 4 are schematic developments of parts of the cylinders of Figs. 1 and 2, showing several of the exchange alphabets thereof in full;

Fig. 5 is a block diagram of a telegraph station incorporating the invention;

Fig. 6 is a top plan view of a translating device according to my invention, forming part of the station of Fig. 5;

Fig. 7 shows, on a larger scale, a side elevation of one of the code disks of the device illustrated in Fig. 6;

Fig. 8 is a section taken substantially on the line VIII-VIII of Fig. 7;

Fig. 9 shows a variety of code profiles adapted to be used-with the disk of Figs. 7 and 8; and

Fig. 10 is a perspective view of part of the mechanism shown in Figs. 6 and 7.

Reference is first made to Figs. 1-4 for a fuller understanding of the principles of my invention previously outlined. A transmitting cylinder, Fig. l, and a receiving cylinder, Fig. 2, are each divided into two halves designated A and B, each half being subdivided into thirteen angular positions designated 1 through 13. The two cylinders are identical, each carrying on its twenty-nine component disks (cf. Figs. 3, 4) a set of twenty-six exchange alphabets of twenty-nine characters (the twentysix letters of the international alphabet plus the three umlauts A, 5, U) occupying the twenty-six angular positions marked 1-13 (A) and 1-13 (B). The complete exchange alphabets of positions 6l2 (A) and 6-12 (B) are illustrated in Figs. 3 and 4, respectively, which also show a set of twenty-nine keys marked with the twentynine letters of the clear or uncoded alphabet.

From a comparison of Figs. 1 and 2 it will be seen that the cylinders of the two stations are relatively offset so that positions 1--13 (A) on the sending cylinder (Fig. 1) correspond to positions 1-13 (B) on the receiving cylinder (Fig. 2) and vice versa. Assuming that the transmitting operator desires to send out the word Berlin, that the transmitting and receiving cylinders are initially adjusted to an operating position corresponding to position 6 (A) and 6 (B), respectively, and that each cylinder is arranged (as more fully described hereinafter) to advance to the next angular position after each translating step, then the operation will proceed as follows: Depression of the key B at the transmitter, in position 6 (A) of its cylinder, results inthe transmission of letter C to the receiving station, whereupon the cylinder advances to position 7 (A) and the letter O is transmitted in response to depression of the key E; in analogous manner the letters R, L, I and N will thereafter be translated into letters M, R," H' and A as the cylinder rotates through positions 8 (A), 9 (A), 10 (A) and 11 (A). At the receiving end, the operator depresses key C in position 6 (B) of the cylinder, in

accordance with the first letter of the incoming message, and obtains the clear letter B, whereupon the cylinder advances into position 7 (B); the operator next depresses the key 0, obtaining the letter B, and so on, until the entire word Berlin" has been spelled out.

Fig. shows a transmit-receive code translator 10, a monitoring printing receiver 11 coupled to the translator 10, a code printing receiver 12 and a switch 13 adapted to connect either the combination of units 10, 11 or the receiver 12 to a telegraph line 14 lea-ding to an identical distant station. With the switch 13 in the position illustrated, translator and monitoring receiver 11 are connected to the line 14 and the equipment is ready to send out coded messages in the manner described, a record of the transmitted code message being simultaneously made by, the unit 11. If a message is to be received, switch 13 is thrown into its alternative position in which the receiver 12 is connected to the line 14; the coded message appearing in the output of that receiver is then fed into the translator 10, either manually or by automatic means not shown, and can be read in clear form at the monitoring unit 11. It will be understood that the line 14 is representative of a cable, radio link or other suitable communication channel interlinking the two stations involved. The printing receivers 11 and 12 may be conventional start-stop receivers, e. g. of the type described inU. S. Patent No. 2,494,232, responsive to five-element pulse code combinations produced with the aid of profiles as shown in Fig. 9(b).

Figs. 6-8 and- 10 show details of construction of the translator 10 so far as necessary for an understanding of my invention. Mounted rotatably on a base 20 is a tubular shaft 21 carrying a set of thirteen disks 22 together constituting the translating cylinder. Shaft 21 is shown provided with a key 23 adapted to orient the several disks 22 in relatively fixed angular positions; thus the disks 22, which may be normally retained on the shaft by set screws or equivalent fastening means (not shown), may be rearranged on the shaft in any desired order so as to increase the versatility of the coding system.

A set of twenty-six typewriter keys 24, one for each letter of the standard international alphabet, are associated with. the thirteen disks 22, there being two keys provided for each disk. The keys 24 are pivoted on an axle 25 and bear upon a stepping bar 26 which is urged upwardly by one or more restoring springs (not shown). An extremity of the stepping bar 26 carries a pawl 27 engaging a ratchet 28 which drives the shaft 21 over a gear train 29; the gears of the train 29 may be replaceable, or means for changing its effective gear ratio may be provided, for the purpose of selectively varying the angle through which shaft 21 is rotated whenever a key 24 is depressed.

Each disk 22, as shown in Fig. 8, comprises two halves 22a, 22b placed side by side and carrying respective sets of code profiles 30 on their outer faces. The code profiles on each disk half 22a, 22b are of conductive material and form projections extending into the path of scanning fingers 31 provided on the two keys 24 which flank the respective disk 22. Fig. 7 shows how each disk is provided with twenty-seven radially extending, uniformly spaced profiles 30 designated 1A through 13A, 13 through 133 and 0; the spaces between these profiles may be filled with cast material. The two disk halves 22a, 226 are held together by a retaining ring 32 and a hub member 33. 7

Figs. 6 and 10 show how a circuit can be established between a source of current, illustrated schematically as a battery 34, and the line 14 by way of disks 22 and keys'24. Whenever the contact finger 31 of a key 24 engages one of the projections of a profile 30, this circuit extends from source 34 over shaft 21, the corresponding disk 22', profile 30, key 24, axle 25 to line 14; The circuit also includes a -circuit"breaker operated from the ratchet 28, indicated schematically at 35, which interrupts the connection whenever the ratchet is rotated by the depression of a key 24, As a result, the circuit will be intermittently completed only during the restoring movement of a depressed key, at which time a train of current impulses determined by the shape of an opera tively positioned code profile 30 will be transmitted over the line 14 as the profile is scanned by the finger 31 of the associated key.

Fig. 9 illustrates three representative types of code profiles adapted to be used with a system accordingto the invention. Profile 30a in Fig. 9(a), representing the formation dot-dash-dot-dot, corresponds to the letter L in a system using the international telegraphy code; all the profiles 30 shown more particularly in Figs. 7 and 8 are of this character. Profile 30b in Fig. 9(b), representing the formation mark-mark-space-markmark-mark, corresponds to the letter L in the fiveelement Baudot code, the final mark being the stop element of said code; it will be understood that other fiveelement or related permutation codes, such as the Murray or Siemens codes, may be utilized in similar manner. Profile 30c in Fig. 9(c), representing a long marking condition followed at long intervals by several short marking conditions, is adapted to reproduce the letter L in a facsimile system of the Hellschreiber type. From these examples it will be apparent that a large variety of code profiles are suitable for use in the system of my invention.

The angular position designated 0 represents an uncoded or clear alphabet, i. e. a row of code profiles representative of the very letters which are marked on the associated keys 24. It will be noted that this clear" alphabet is inserted between the first exchange alphabet 1A of the A series and the last exchange alphabet 13B of the B series; at the receiving end, accordingly, a similar clear alphabet will be inserted between the first exchange alphabet of the B series and the last exchange alphabet of the A series of the otherwise identical translating cylinder. The disk halves 22a, 22b shown in Fig. 8 are associated with the L and M keys 24 which are partly visible in the same figure, hence the profiles 30 shown in the lower portions of these disk halves represent the telegraphy symbols for the letters L and M, respectively.

When any key 24 is actuated, stepping bar 26 is depressed and pawl 27 rotates ratchet 28 which momentarily breaks the line circuit at 35. At the same time, dependent upon the transmission ratio provided by gear train 29, this movement is transmitted to shaft 21 and disks 22 to advance the latter through one or more angular steps; thus the finger .31 of key 24 in Fig. 7, which is shown to register with profile 30 in position 1113, will scan a different code profile when the key is released, e. g. the one in position 12B, 13B or 1A. With a total of twenty-seven available angular positions, the cylinder may be stepped through one, two, four, five or seven positions at a time, or through any number of such positions which is not a factor of twenty-seven or a multiple of such factor, without omitting any of the twentyseven exchange alphabets (including the clear alphabet in position 0). If a fourteenth exchange alphabet is added in both the A and the B series, then the total number of alphabets will be twenty-nine, thus a prime number, and the rate of advance between letters may be varied to an even greater extent.

In the normal operation of the device 10, when the same is used for the coding of outgoing or the decoding of incoming messages, the advance of the cylinder will thus take place during the downstroke of a key 24 while the scanning occurs during the subsequent upstroke thereof. When the gear train 29 is removed or otherwise inactivated and the cylinder rotated to position 0, a clear or uncode'd message text may be transmitted:

By way of specific example, let its consider the trans mission of a message with the gear train 29 arranged to advance the transmitting cylinder of Fig. 7 by two rows whenever a key 24 is depressed. point is so selected that the fingers 31 register with, say, the profiles in position 1A, then, in accordance with the foregoing, shaft 21 will have moved one of the profiles at 3A into the path of the finger of the actuated key when the latter is released, hence the first letter is translated according to the code of row 3A. When the next key is actuated, disks 22 are stepped by another two rows, thus the second letter is translated according to the code of row 5A. In likemanner the rows 7A, 9A, 11A and 13A of the left-hand cylinder half (as viewed in Fig. 7) are subsequently rendered operative for the transmission of successive letters. At the receiving station, where by pre-arrangement the operator has started from position 1B of a similar cylinder, the first six letters of the incoming message are re-translated in like manner by the successive use of the exchange alphabets in positions 3B, 5B, 7B, 9B, 11B and 13B.

When the seventh letter is to be sent, finger 31 of the depressed transmitter key 24 finds itself in register with a profile in row 2B, hence with a profile on what originally was regarded as the receiving half of the transmit-receive cylinder. The next five letters are similarly translated by means of codes in positions 48, 6B, 8B, 103 and 123 respectively. At the receiver, on the other hand, retranslation takes place by means of codes in positions 2A, 4A, 6A, 8A, A and 12A, thus through the use of the original transmitting half of the combination cylinder.

When the thirteenth letter is being transmitted, finger 31 scans a profile of the clear" alphabet in position 0. Since, as noted above, the clear" alphabet of the cylinder at the receiving station is inserted between positions 13A and 1B, the receiver in translating this thirteenth letter is likewise stepped onto a clear code profile, thus the thirteenth letter is transmitted and received without change.

In the next revolution of the cylinder at the transmitting station, the hitherto unused rows 2A, 4A etc. through 12A and 1B, 3B etc. through 13B are utilized in succession, the apparatus then returning to the starting position mentioned above. Analogously, the counterparts 2B, 4B etc. through 12B and 1A, 3A etc through 13A are now used at the receiving end. It will be understood, therefore, that by virtue of the present invention the original division of a cylinder into transmitting and receiving halves is only for reference purposes and that both halves are utilized for coding as well as decoding.

The invention is, of course, not limited to the specific numeric or alphabetic arrangements illustrated, nor to the particular details of construction or circuit elements shown and described, inasmuch as many modifications or adaptations thereof will readily occur to those skilled in the art without constituting a departure from the scope of the invention as defined in the appended claims.

I claim:

1. A translating device for code communication systems, comprising a rotatable cylinder provided with two sets of angularly spaced rows of code elements, all of said rows being axially aligned with one another, each row representing a coded translation of a set of message characters, the rows of one set of code elements being the transmit-receive counterparts of respective rows of the other set of code elements, and means for sequentially rendering operative each of said rows by rotating said cylinder into a succession of different angular positions, the rows of one set following one another in the same order as their respective counterparts in the other set.

2. A translating device for converting the characters of a normal alphabet into characters of a succession of If the starting exchange alphabets, in accordance with respective rows of a predetermined coding table, and for reconverting the characters of said exchange alphabets into those of said normal alphabet, in accordance with respective rows of a predetermined decoding table which are the transmit-receive counterparts of corresponding rows of said coding table, comprising a rotatable cylinder provided with two sets of angularly spaced rows of code elements, all of said rows of code elements occupying the same axial position on said cylinder, each row of one set corresponding to a' respective row of said coding table, each row of theother set corresponding to a respective row of said decoding table, the rows of one set following one another in the same order as their respective counterparts in the other set, a set of actuating members axially spaced along said cylinder, each of said members representing a character of said normal alphabet, scanning means on said actuating members selectively engageable with corresponding code elements of each row in different angular positions of said cylinder, and stepping means for rotating said cylinder progressively through all of said angular positions between successive actuations of any of said members.

3. A translating device according to claim 2, wherein said cylinder is further provided with a row of "clear code elements corresponding to the characters of said normal alphabet, said row of clear code elements being inserted between the last row of one set and the first row of the other set.

4. A translating device according to claim 3, wherein the total number of said rows of code elements is a prime number.

5. A translating device according to claim 2, wherein the rows of each set follow one another in immediate succession.

6. A translating device according to claim 2, wherein said cylinder comprises a shaft and a 'set of disks mounted on said shaft, each of said disks carrying a plurality of said code elements in angularly spaced positions.

7. A translating device according to claim 6, wherein said code elements are electrically conductive profiles extending radially along at least one face of each disk, said profiles being engageable by said scanning means of a respective one of said actuating members, said scanning means comprising conductor means intermittently engageable with said profiles and adapted to close an electric circuit upon engagement therewith.

8. A translating device according to claim 7, wherein at least some of said disks are provided with a set of said profiles on opposite faces, the profiles on each face co-operating with the scanning means of a respective one of said actuating members.

9. A translating device according to claim 7, wherein said profiles are shaped according to the elements of a dot-dash telegraphy code.

10. A translating device according to claim 7, wherein said profiles are shaped according to the elements of a permutation code.

11. A translating device according to claim 7, wherein said profiles are shaped according to the elements of a facsimile reproduction system.

12. A translating device according to claim 7, wherein said disk face is provided with a fusible mass, said profiles being imbedded in said mass.

13. A translating device according to claim 6, wherein said disks are interchangeably mounted on said shaft.

14. A code communication system comprising a transmitting station and a receiving station, each of said stations including a translating device comprising a rotatable cylinder provided with two sets of angularly spaced rows of code elements, all of said rows being axially aligned with one another, each row representing a coded translation of a set of message characters, the rows of one set of code elements being the transmit-receive counterp'arts of respective rows of the other set ofcodeelements, andmeans for sequentiallyrendering operative eachof said rows by rotating said cylinder into a successien of different angular positions, the rows of one set following one another in the same order as their respective counterparts i-n--the other set; and a com'mun-i cation channel interconnecting said'stations.

15. A code communication system accordingto claim 14, wherein. said message characters are the character's ofa normal alphabet, each of said cylinders being further provided with a row of clear code elements corresponding to the characters of said normal'alphabet, said row of clear code elements being i'nserted'between the last-row of oneset and the first row of the other set, said cylinders at both of said stations being identical except: for; an inversion-of therelative positions of said sets of code elements Withrespectto said row of-cleafl code elements.

References Cited in the file of this patent UNITED STATES PATENTS 10 1,912,983 Jipp et al. June 6,1933

2,269,341 Hebern Ian. 6, 1942 FOREIGN PATENTS 341,073 Great Britain Jan. 5, 1931 

